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  <title>Document</title>
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<body>
  <script>
    let p = new Promsie((resolve, reject) => {
      resolve('ok');
    });
    // r => {throw r}    v => v
    // 
    p.then(v => {}).then(v => {}).then(v => {}).catch(reason => {})
    p.catch(v => {}).catch(v => {}).catch(v => {}).then(v => {})

    await req();
    await reqxx();
    await reqxxx();

  </script>
</body>
</html>